Automatic safety latch



Sept. 18, 1928.

F. M. SCHULTZ AUTOMATIC SAFETY LATCH Filed Nov. 25, 1927 INVENTOR F'rei cfluliz.

ATTORNEY Patented Sept. 18, 1928.

UNETED STATES FRED Iii. SCHULTZ, OF DETROIT, MICHIGAN.

AUTOMATIC SAFETY LATCH.

Application filed November 25, 1927. Serial No. 235,473.

My invention relates to a new and useful improvement in an automatic safety latch of the alarm type adapted for mounting on a building in which a door is hung so as to permit a slight opening of the door and preventing further opening of the door.

It is an object of the present invention to provide a safety latch of this kind having an alarm mechanism whereby upon an attempted opening of the door an alarm will be sounded.

It is another object of the present invention to provide a device of this class having a releasable trigger arranged and constructed so that the fastening device attached thereto may be utilized for cocking the trigger.

Another object of the invention is the provision of a device of this class having a housing adapted to co-operate with a locking member. the housing being provided with a pairof openings for the reception of the locking member, the engagement of said locking member in one of said openings being aoapted for releasing a trigger in said housing.

Another object of the invention is the provision in a device of this class of a separable explosive cap carrying member.

Other objects will appear hereinafter.

The invention consists in the combination and arrangement of parts hereinafter described and claimed.

The invention will be best understood by a reference to the accompanying drawings which form a part of this specification and in which,

Fig. 1 is a front elevational View of the invention showing it applied to a door and casing shown in fragment.

Fig. 2 is a view similar to l with the outer wall of the housing cut away.

Fig. 3 is a sectional view taken on line of Fig. 2.

Fig. 4 is a perspective view of the explosive cap carrying member.

In the drawings I have illustrated the in vention used with a door casing 7 adapted to engage a door 7. Mounted on the door '2 is a housing 8 having a circular opening 9 formed therein leading from which is the elongated slot 10. A similar opening 11 is provided in the housing leading from which is the elongated slot 12. Mounted on the casing 7 is aplate 13 connected to which is one and of a chain or other fastening member 14 carrying at its free end a plate 15 from wh ch is punched a locking tongue 16, this loosing tongue being cut away at its base to )FJOVIClB shoulders and a restricted portion the restricted portion engaging in the elon gated slots 10 and 12 so that when enga ed in these slots, the locking tongue 16 caniiot be removed therefrom until the same is slid into either the opening 9 or the opening 11.

.hehousing 8 13 provided at one side with an opening 1'? into which may be thrust the plate 18 having its upper end 19 angularly turned and doubled upon itself as at 2O. the doubled over portion being provided with an eyelet 21 which extends beyond the edge of the housing 8. Mounted on one face of the plate 18 is a boss 21 which serves as a support for an explosive cap, the entire separable member constituting an explosive cap carrier.

Secured to the inner wall of the housing 8 ad acent its base is a spring plate 38 behind Wl11('ll one edge of a plate 18 is adapted to engage, this member 38 servin to prevent dislrxlgn'ient of the explosive ca; carrier the doubled over portion providing a spiing progection which when the plate 18 is thrust fully inwardly is normally under tension.

Mounted in the housing 8 is a plate 22. one end 23 of which is turned outwardly and provided with a slot 24- formed therein: The other end of the plate 22 is turned outwardly to provide the outwardly extending flange 2 5 which is also provided with a slot- 26 formed therein, the flange 25 being shorter than the flange 23 and these flanges, together with the plate 22. forming a U-shapod member.

Projected through the opening 24 and slidable in the slot 26 is a plate Q'fhaving at its fOl'V-itlld end the outwardly extending legs 28 and positioned between which is the which serves as a contact member or striker. This plate 27 is slitted to provide a rearwardly extending finger 31 and the rearwardly extending leg 32 in which is formed on the lower edge a slot 82. the lower edge of this leg 32 normally engaging the base of the slot The rear end of the leg 39. is singularly turned as at 33. Coiled about the leg 32 and engaging at one end the flange portion 25 of the plate 22 and at its opposite end the base of the slits in the base of the plate 27 is a coil spring34 normally tending to thrustthe plate 27 into the position shown i dotted lines in Fig. .2 so that wh e plate 27 is in the position shown in full lines in Fig. 2, the spring 34 will be under considerable compression.

A leg 35 projects rearwardly of the plate 27 and is provided at its end with the laterally turned portion 36. Formed on the under-surface of the plate 27 adjacent its forwe rd end is an arcuate surface 3? to provide a sort of depression in which the lock head or tongue 16 may engage when positioned in the opening 11.

After the device has been mounted as described and it is desired to use the same as a night latch and at the same timeas a burglar alarm to indicate an attempted opening of the door 7, the tongue or head 16 would be inserted in the opening 9 and drawn along the slot 10 engaging the laterally turned portion 36 and moving the plate 27 from the position shown in dotted lines in Fig. 2 to the position shown in full lines, the notch 32 serving to lock the plate against forward movement and retain the spring 34 under compression. The explosive cap carrying member may then be Withdrawn and an explosive ca) be positioned on the boss 21. The head or tongue 16 is then removed through the opening 9 and placed in engagement with the opening 11. Any attempted opening of the door will then effect a moven'lent of the tongue or head 16 along the slot 12 and this movement will rock the plate 27 upwardly sufficiently to disengage the flange from the notch 32 and permit its forward move- I ment in response to the pressure of the spring 3-1, this movement of course being a rapid one so that when the boss contacts with the explosive cap the same will be exploded. A t the same time the engagement of the tongue or head 16 in the slot 12 will serve to lock the door against opening movement beyond the limits determined by the length of the chain 14.

It is obvious that when it is desired to use the lock in the daytime, the openings 11 or 9 may be used desired without any untoward or damaging action on the apparatus, the boss 30 and the boss 21 being made of sulli cicntly hard material to withstand the impact which would result from their engagement, should the plate 27 be released while no cap was on the boss 21'.

It is, believed obvious that the plate 2-7 acts as an exploding hammer 0r plunger.

The simplicity of the device is believed obvious and the economy of structure and durability and efliciency of the device are further objects sought to be obtained.

Vhile I have illustrated and described the preferred form of my invention I do not wish to limit myself to the precise details of structure shown, but desire to avail myself of such variations and modifications as come within the scope of the appended claims.

Having thus described my invention what aim as new and desire to secure by Letters cut is:

In a lock of the class described, a hensin having a pair of spaced enlarged openings formed in one side thereof and provided with an elongated slot extending into each of said openings; a plun er slidably mounted in housing; a spring engaging said sale plunger and normally pressing the same toward one side of said housing, said plunger having a notch formed therein; means in said housing for engaging in said notch and look ing the same against movement in response to the pressure of said spring; a separable member insertable into said housing; a boss on sait separable member for supporting an explosive cap in the path of said plunger; a separable member for engaging in said slots and sliding therein, said member while sliding in one of said slots releasing said plungor for n'iovemont in response to said spring; and a laterally turned portion on one end of said plunger, said separable member while sliding in the other of said slots engaging said laterally turned member and serving to retract said plunger against the pressure of said spring.

2. in a device of the class described, a housing; a plate mount-ed in said housing; an outwardly projecting flange at opposite ends of said plate, one of said flanges having an opening formed therein, and the other of said flanges having a slot formed therein register ing with said opening; a plunger slidably mounted in said opening and en a ing in said slot; a striking portion on said plunger; an enplosive cap supporting member in said housing registering with said striking portion; a spring normally tending to thrust said striking portion into engagement with said cap simporting member, said plunger having a notch formed therein engaging with the lower edge of said slot for locking said plunger in retracted position against the tension of said spring.

3. In a device of the class described, a housing; a plate mounted in said housing; an outwardly projecting flange at opposite ends of said plate, one of said flanges having an opening formed therein, and the other of said flanges having a slot formed therein registering with said openin a plunger slidably mounted in said opening and engaging in said slot; a striking portion on said plunger: an explosive cap supporting member in said housing registering with said striking portion: a spring normally tending to thrust said striking portion into engagement with said cap supporting member. said plunger having a notch formed therein engaging with the lower edge of said slot for locking said plunger in retracted position against the tension of said spring, said housing having a pair of enlarged openings formed therein, each communicat-ing with an elongated slot; and asep ill) arable member engageable in said slots, the slidable movement of said member in one of said of slots ettecting a release of said plunger.

4. in a de *ice of the class described, a housing; a plate mounted in said housing; an outwardly projecting flange at opposite ends of said plate, one of said flanges having an open ing tormed therein, and the other ot said 'langes having a slot formed therein registering with said opening; a plunger slidabl mounted in said opening and engaging in said slot; a striking portion on said plunger; an explosive cap supporting member in said housing registering with said striking portion; a spring normally tending to thrust said striking portion into engagement with said cap supporting member, said plunger having a notch formed therein engaging with the lower edge of said slot tor locking said plunger in retracted position against the tension of said spring, said housing having a pair of enlarged openings termed therein, each communi 'ating with an elongated slot; a separable member engageable in said slots. the slid able movement of said member in one of said slots ell'ecting a release of said plunger; a laterally projecting portion on said plunger, the slidable movement of said member in the other of said slots engaging said laterally projecting portion and retracting said plunger against the compression of said spring.

5. in a device of the class described, a housing having a pair of enlarged spaced openings formed therein, each communicating with an elongated slot; a plate mounted in said housing: a flange at each end of said plate, one of said flanges having an elongated opening formed therein in registration with an elongated slot formed in the other flange; a plunger slidabl; mounted in said opening in said flange and engaging in said slot in said flange: a striking portion on said plunger; a separable explosive cap supporting member projectable into said housing for retaining said cap in the path of said striking portion; means for resisting removal of said separable member from said housing: a lateral projection on said plunger. said separable mem ber, while riding in one of said slots in said housing engaging said lateral projection and retracting said plunger against the compressioil of said spring. and while riding in the other of said slots engaging the lower end of said plunger and releasing the same for movement in response to the pressure of said sprin In testimony whereof I have signed the 'l oregoing specification.

FRED M. SCHULTZ. 

